Improvement in plow-clevises



G. ERKSON.

V Plow-Glevis.

No. 7,651. v Patented Sept 17, 1850.

N.PETER$, FHOTO-UTHOGRAF'HER, WASHINGTON. D c

UNITED STATES PATENT FFICEO GERRETT ERKSON, OF

HOBART, NE? YORK.

IMPROVEMENT IN PLOW-CLEVISES.

To all whom it may concern:

Be it known that I, GERRETT ERKSON, of the town of Hobart, county of Delaware and State of New York, have invented a new and useful machine called a GentenDraft Double- Gage Clovis, and Ido hereby declare that the following isa full, clear, and exact description of movement of the ordinary clevis and of the double sets of teeth and cavities by which the position of the slot-bar is secured against the end of the beam-immovable except when intentionally released-that I call my machine a center-draft double-gage clevis.

The construction of my clevis will be understood by reference to the drawings, in which Figure 1 is a side elevation of a. part of plow beam and clevis; Fig. .2, a front or end view of the same. Fig. 3 is an end view of the castiron square socket A which goes upon the end of the plow-beam, with the gage-ridges r r r, 850., and the grooves s s .9 arranged radially around a common center. The teeth or ridges 1' are seen to increase in breadth from the center outward. Fig. 4 is a back viewof the slotted bar B of the clevis, having on each side lozenge-shaped teeth tt t with their longest diagonals across the breadth of the clevis-bar. These teeth are so formed and arranged as to match into the spaces 8 s s, &c., and receive between them the ridges r 1'7, &c., of the box or socket A, Fig. 3. As seen in' Fig. 1, not less than three of the ridges r r r are on each side in contact with the teeth t t t, and since all the teeth as well as the ridges are made sloping, the tightening up of the screw 0 by turning the forked end I and forcing it into the sunken nut 12, this operation brings every tooth to a full hearing, such as effectually to prevent slipping in any direction. Fig. 5 is an end view of the square socket A, having instead of the radial ridges of Fig. 3 a circle of conical cavities, 0 c c, &c., to receive conical points along the sides of the slotted bar. Fig. 6 is the slotted bar 13 with the above-mentioned conical points seen at tt t, &c. 'When this bar is applied to A, Fig. 5, four or six of the points it will enter corresponding cavities in A. If the curved end row of the points t be brought into the circle of cavities in A, all four of the points will match into corresponding holes, and at the same time two points t along the lateral rows will be found in bearings. When neither end of the bar is over any part of the circle of cavities four points only will comeinto action at the same time.

In order to give a broader bearing to the head of the screw 0, I place between it and the clevis-bar B, Fig. 1, the washer D.

In Figs. 1, 2, 4, and 6, H represents the hole in the clevis through which passes the draftrod from the posterior part of the beam of the plow.

From the above description it is made apparent that B may be in any desired position with reference to the axis of the plow-beam, and that whether made with the radial ridges r 1, Fig. 3, and the rhombic teeth t t, Fig. 4, or with the circle of conical holes 0 c, Fig. 5, and the conical teeth t t, Fig. 6, the machine will in both modifications present the same property of universality of directing power and the entire absence of all tendency to slide, not in any case depending on the mere friction of surfaces created by the pressure of the screw to retain it in place.

I do not limit myself to the particular form of holes in the socket, Fig. 5, and of teeth in Fig. 6, nor will it be necessary that the holes should always be on the socket and the teeth on the slotted bar; butthe reverse may be the arrangement, if preferred. The principle is, however, still preserved of making two such series of prominences and depressions, one on the fixed socket and the other on the movable bar which guides the draft rod or chain, that the two may be set in any required position throughout the circle and at any distance of the draft rod from the center ofthe beam, while the prominences and cavities shall in every position preventthe slipping of the clevis-bar by resistances independent of mere friction. In both modifications it is evident that no slipping or derangement can take place without breaking away the prominences of either the socket or the slotted bar, or of both.

I am aware that attempts have been made to construct clevises having notches in one direction. while in other directions the continement of the clevis depended on the friction created by a pressure of one part of the apparatus on another. This defect my clevis is intended to obviate, whileit attains the purpose of gaging the position circularly and the distance radially from any given position of the axis of the plow-beam. I commonly make my clevis, except the tightening-screw O and nut 02, of cast-iron, but do not limit myself to any particular material.

1 am aware that plow-clevises having radial teeth or cogs on the front of a socket and parallel ridges to slide between them have already been used; but these I do not claim, since they are, in my estimation, defective for want of numerous bearing-points and from not presenting t0 the longitudinal motion of the parallel ridges any resistance except friction.

Having thus described my invention, what I claim as new, and desire to secure by Letters Patent, is-

1. So making a clevis with teeth or promi- Y from either sliding or ret olving in any direction without breaking the continuity of materials of which the parts are composed.

2. In combination with a series of radial ridges or a circle of cavities on the end of a clcvis-socket fixed at the extremity of the plowbeam, a series of teeth or conical points on a movable clevis-bar, so adjusted to each other that the guidehole of the clevisbar may be held in any required position and at any necessary distance from the axis of the beam without relying on friction of the surfaces to prevent slipping, in the manner and for the purpose herein set forth.

Gunner]: ERKSON.

Witnesses:

WALTER R. JoHNsoN, J OHN L. SMrrrr. 

